ABSTRACT
Transcranial magnetic stimulation (TMS) is unique among the current brain stimulation techniques because it is relatively non-invasive. TMS markedly differs from vagus nerve stimulation, deep brain stimulation and magnetic seizure therapy, all of which require either an implanted prosthesis or general anesthesia, or both. Since its rebirth in its modern form in 1985, TMS has already shown potential usefulness in at least three important domains-as a basic neuroscience research instrument, as a potential clinical diagnostic tool, and as a therapy for several different neuropsychiatric conditions. The TMS scientific literature has now expanded beyond what a single summary article can adequately cover. This review highlights several new developments in combining TMS with functional brain imaging, using TMS as a psychiatric therapy, potentially using TMS to enhance performance, and finally recent advances in the core technology of TMS. TMS' ability to non-invasively and focally stimulate the brain of an awake human is proving to be a most important development for neuroscience in general, and neuropsychiatry in particular.
Subject(s)
Electromagnetic Fields , Mental Disorders/therapy , Movement Disorders/therapy , Pain Management , Physical Therapy Modalities/methods , Transcranial Magnetic Stimulation/therapeutic use , Animals , Brain/physiopathology , Brain Mapping , Humans , Magnetic Resonance Imaging , Mental Disorders/physiopathology , Movement Disorders/physiopathology , Pain/physiopathology , Treatment OutcomeABSTRACT
The key to success with any ophthalmic spectacle prescription is not only the accurate determination of the refractive prescription, but the proper selection and fitting of the ophthalmic frame and lenses. Proper selection and fitting are especially important with bifocals, trifocals, or progressive lenses, which present many variables other than inaccurate interpupillary distance measurement that can lead to patient dissatisfaction. This article discusses fitting procedures for patients with new or existing multifocals. It reviews how to determine proper multifocal segment heights; and calculate distant decentration, inset, and total inset measurements; and it addresses issues involving variations in frame size and patient temperament.
Subject(s)
Eyeglasses , Prosthesis Fitting/methods , HumansABSTRACT
When changing to bifocal lenses from distance anisometropic lenses, presbyopic patients may experience diplopia when attempting to do close work. Prescription failure can be dramatically reduced by utilizing the procedures outlined in this article. Why would a patient experience diplopia when attempting to read with bifocals? The diplopia may simply be a result of the optical difference in power between the two lenses. Anisometropia creates a disparity in the size of the retinal image as well as a prismatic imbalance when looking away from the optical center. A practical approach to coping with these problems is recommended.
Subject(s)
Anisometropia/therapy , Eyeglasses , Presbyopia/therapy , Accommodation, Ocular , Diplopia/prevention & control , Humans , Vision DisparityABSTRACT
Why would a patient complain of "fuzzy and uncomfortable" vision with a variety of glasses? Perhaps because the practitioner has failed to take facial asymmetry into account. Methods of measuring facial asymmetry and optically correcting for it are discussed.
